Prevalence of pfmdr1, pfcrt, pfdhfr and pfdhps mutations associated with drug resistance, in Luanda, Angola

<p>Abstract</p> <p>Background</p> <p>Malaria is the infectious disease causing the highest morbidity and mortality in Angola and due to widespread chloroquine (CQ) resistance, the country has recently changed its first-line treatment recommendations for uncomplicated malaria, from CQ to artemisinin combination therapies (ACT) in adults, and sulphadoxine/pyrimethamine (S/P) in pregnant women. Loss of SP sensitivity is, however, progressing rapidly in Africa and, in this study, were investigated a number of molecular markers associated to CQ and S/P.</p> <p>Methods</p> <p>Blood samples were collected from 245 children with uncomplicated malaria, admitted at the Pediatric Hospital Dr. David Bernardino (HPDB), Angola, and the occurrence of mutations in <it>Plasmodium falciparum </it>was investigated in the <it>pfmdr1 </it>(N86Y) and <it>pfcrt </it>(K76T) genes, associated with CQ resistance, as well as in <it>pfdhfr </it>(C59R) and <it>pfdhps </it>(K540E), conferring SP resistance.</p> <p>Results</p> <p>The frequencies of <it>pfmdr1 </it>mutations in codon 86 were 28.6% N, 61.3% Y and 10.1% mixed infections (NY). The frequency of <it>pfcrt </it>mutations in codon 76 were 93.9% K, 5.7% T and 0.4% mixed infections (KT). For <it>pfdhfr </it>the results were in codon 59, 60.6% C, 20.6% R and 18.8% mixed infections (CR). Concerning <it>pfdhps</it>, 6.3% of the isolates were bearers of the mutation 540E and 5.4% mixed infections (K540E).</p> <p>Conclusion</p> <p>The results of this epidemiologic study showed high presence of CQ resistance markers while for SP a much lower prevalence was detected for the markers under study.</p

INCIDENCE OF TRAVELERS’ DIARRHEA AMONG JAPANESE VISITING THAILAND

A cross-sectional survey of 327 Japanese short-term travelers (≤3 weeks) arriving in Bangkok, Thailand was conducted to assess the incidence of travelers’ diarrhea (TD) as well as their symptoms and treatment-seeking behaviors. The incidence of the first episode of TD (FTD) was ascertained retrospectively by questionnaire. Reported by 69 travelers, FTD clustered within the first 8 days of arrival in Thailand, and the incidence rate varied from 2% to 8% with the highest incidence on the third day.Cumulative probability of FTD was 19% for those arriving in Thai directly from Japan, 42 % for those arriving via Southeast Asia, and 25% for those arriving via other regions at Day 7 by the Kaplan-Meier survival analysis. Log rank test revealed a higher FTD risk for travelers arriving via other Southeast Asian countries than for those arriving directly from Japan (P < 0.005). Of all the 69 FTD episodes, 33% had classic TD defined as ≥3 unformed stools per 24 hours with at least one accompanying symptom, 49% had moderate TD defined as ≤2 unformed stools with at least one additional symptom or more unformed stools without additional symptoms, and 17% had mild TD defined as with ≤ 2 unformed stools without additional symptoms. Cumulative probability of FTD at Day 7 was 12% for classic TD, 25% for classic plus moderate TD and 30% for all the TD. More than 38% of travelers with diarrhea took medicine brought from Japan. Among travelers with classic TD, 35% bought medicine in Thailand, whereas 47-50% of travelers with moderate and mild TD took only rest without any treatment

Mapping of schistosomiasis and soil-transmitted helminths in Namibia: The first large-scale protocol to formally include rapid diagnostic tests

Background: Namibia is now ready to begin mass drug administration of praziquantel and albendazole against schistosomiasis and soil-transmitted helminths, respectively. Although historical data identifies areas of transmission of these neglected tropical diseases (NTDs), there is a need to update epidemiological data. For this reason, Namibia adopted a new protocol for mapping of schistosomiasis and geohelminths, formally integrating rapid diagnostic tests (RDTs) for infections and morbidity. In this article, we explain the protocol in detail, and introduce the concept of 'mapping resolution', as well as present results and treatment recommendations for northern Namibia.Methods/Findings/Interpretation: This new protocol allowed a large sample to be surveyed (N = 17 896 children from 299 schools) at relatively low cost (7 USD per person mapped) and very quickly (28 working days). All children were analysed by RDTs, but only a sub-sample was also diagnosed by light microscopy. Overall prevalence of schistosomiasis in the surveyed areas was 9.0%, highly associated with poorer access to potable water (OR = 1.5, P<0.001) and defective (OR = 1.2, P<0.001) or absent sanitation infrastructure (OR = 2.0, P<0.001). Overall prevalence of geohelminths, more particularly hookworm infection, was 12.2%, highly associated with presence of faecal occult blood (OR = 1.9, P<0.001). Prevalence maps were produced and hot spots identified to better guide the national programme in drug administration, as well as targeted improvements in water, sanitation and hygiene. The RDTs employed (circulating cathodic antigen and microhaematuria for Schistosoma mansoni and S. haematobium, respectively) performed well, with sensitivities above 80% and specificities above 95%.Conclusion/Significance: This protocol is cost-effective and sensitive to budget limitations and the potential economic and logistical strains placed on the national Ministries of Health. Here we present a high resolution map of disease prevalence levels, and treatment regimens are recommended.Peer reviewedEntomology and Plant Patholog

Avaliação da resposta do Plasmodium falciparum à cloroquina, quinino e mefloquina

Nosso estudo envolveu a análise de cepas de Plasmodium falciparum provenientes da Região Amazônica Brasileira, coletadas no Laboratório de Malária da SUCEN. Os estudos "in vitro" foram efetuados com a cloroquina (46 ensaios), quinino (42 ensaios) e mefloquina (51 ensaios). Os resultados mostraram resistência de 100% em relação à cloroquina, 2,4% ao quinino e 31,4% à mefloquina, na análise "in vitro". Sete pacientes foram tratados com quinino isolado e nove com a associação mefloquina + pirimetamina-sulfadoxina, não mostrando correlação com os testes "in vitro"